Gas filling facility for photomask pod or the like

ABSTRACT

A gas filling system includes a work platform installed in a pod storage cabinet and defining an accommodation chamber for holding a photomask pod, a pod detaching mechanism disposed in one side of the work platform and controllable to unlock the locking members of the photomask pod for allowing removal of a cover member of the photomask pod from its support tray, and a displacement mechanism mounted in a second side of the work platform and controllable to separate the support tray and the cover member of the photomask pod for allowing filling of an inert gas into the accommodation chamber.

1. Field of the Invention

The present invention relates to gas filling facility and more particularly, to a gas filling system for SMIF system storage box, for example, photomask pod, which keeps the storage photomask in an airtight environment for the filling of an inert gas so that the filled inert gas maintains excellent cleanliness of the photomask pod.

2. Description of the Related Art

The 21^(st) Century is the era of digitalization where high-tech products have been developed and intensively used in our daily life, bringing a great convenience to human beings. These high-tech products use IC chips for operation control. It is necessary to employ new knowledge and techniques to control high-tech products such as computer, new generation TV, digital stereo system, central control of building, advanced car, aircraft, and other clothing, food, housing and transportation related products. IC chips are most important components parts in high-tech products. An IC chip is comprised of high-precision integrated circuits, and made through a high-precision processing operation on a silicon single crystal in a clean room by means of a photomask and high-precision machines. These high-precision machines are very expensive. During fabrication of wafers, the yield rate determines the profitability of the foundry. Therefore, it is quite important to a semiconductor factory manager to bring up the yield rate for their products.

Further, the novel standardized mechanical interface (SMIF) technology is utilized in a clean room for the fabrication of ICs, which reduces particle contamination by significantly reducing particle fluxes onto wafers. During transportation, storage, and most processing steps, the gaseous media surrounding the wafers is essentially stationary relative to the wafers, and particles from exterior environments cannot enter the wafer environments. The SMIF system of wafer handling reduces wafer particle contamination.

In order to prevent damage to wafers or photomasks, SMIF system storage boxes are used and filled with an inertia gas to deliver wafers or photomasks, preventing oxidation of wafers or photomasks during delivery. A SMIF system photomask pod has a valve device through which gaseous media is filled into the inside space of the photomask pod. FIGS. 10 and 11 shows a prior art design. According to this design, the photomask pod A comprises a port A1, a valve device B mounted in the port A1 and adapted to close/open the port A1, and a spring member C mounted in the port A1 around the valve device B and holding the valve device B in the close position. The valve device B has a downwardly extending insertion hole B1 in communication with the atmosphere, and peripheral air outlets B2. When filling an inert gas into the photomask pod A, the nozzle tip D of the gas pipe from the inert gas source (not shown) is inserted into the insertion hole B1 to lift the valve device B, thereby opening the peripheral air outlets B2 for letting supplied inert gas to pass through the peripheral air outlets B2 into the inside of the photomask pod A. After removal of the nozzle tip D from the insertion hole B1, the spring member C immediately pulls the valve device B back to its former position to close the peripheral air outlets B2. This arrangement has drawbacks. During an inert gas filling operation, the spring member C is moved, thereby causing friction with the peripheral wall of the port A1 and the valve device B. Friction between the spring member C and the peripheral wall of the port A1 or the valve device B invites particle contamination, thereby destructing the cleanliness of the inside storage space of the photomask pod A. Further, the installation of this photomask pod is complicated.

SUMMARY OF THE INVENTION

The present invention has been accomplished under the circumstances in view. It is the main object of the present invention to provide an inert gas filling system for photomask pod or the like, which eliminates the drawbacks of the aforesaid prior art photomask pod design.

According to the present invention, the gas filling system is for filling a photomask pod with a gas. The photomask pod comprises a support tray, a cover member detachably covering the support tray, and locking members for locking the cover member to the support tray. The gas filling system comprises a pod storage cabinet, which has a storage, a work platform, which is installed in the bottom side of the storage of the pod storage cabinet and has an accommodation chamber for accommodating the photomask pod and for filling of a gas in the pod stored therein, a pod detaching mechanism, which is disposed in one side of the work platform inside the v storage cabinet and comprises a power drive and actuating means movable by the power drive to lock/unlock the locking members of the pod, and a displacement mechanism, which is mounted in a second side of the work platform and controllable to move the support tray of the pod relative to the cover member of the pod after unlocking of the locking members of the pod.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevational view of an inert gas filling system in accordance with the present invention.

FIG. 2 is an exploded view of the inert gas filling system in accordance with the present invention.

FIG. 3 is an exploded view of a photomask pod for use with the inert gas filling system according to the present invention.

FIG. 4 is a schematic drawing showing the inert gas filling system installed in a pod storage cabinet according to the present invention.

FIG. 5 is a schematic drawing of a part of the present invention, showing the pod detaching mechanism in action.

FIG. 6 is a schematic sectional view of the present invention, showing a status of the inert gas filling system before the inert gas filling operation.

FIG. 7 is a schematic sectional view of the present invention, showing an inert gas filling status of the inert gas filling system.

FIG. 8 is a schematic sectional view of an alternate form of the inert gas filling system according to the present invention.

FIG. 9 corresponds to FIG. 8, showing the cover member of the pod removed from the support tray.

FIG. 10 is a schematic drawing showing the insert gas filling operation of a photomask pod according to the prior art (I).

FIG. 1110 is a schematic drawing showing the insert gas filling operation of a photomask pod according to the prior art (II).

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1˜5, an inert gas filling system 1 in accordance with the present invention is shown comprising a work platform 11, a pod 12, a pod detaching mechanism 13 and a displacement mechanism 14.

The work platform 11 comprises an accommodation chamber 110, a first opening 111 at the top side of the accommodation chamber 110, a second opening 112 at the bottom side of the accommodation chamber 110, and inert gas filling ports 113 in the accommodation chamber 110. The accommodation chamber 110 is peripherally sealed with an airtight seal means.

The pod 12 is provided at one side, namely, the top side of the work platform 11 for accommodating a storage item (for example, photomask, semiconductor wafer, substrate, circuit board, etc.) 2. According to this embodiment, the pod 12 is a photomask pod for holding a photomask. The pod 12 comprises a support tray 121, a cover member 122 covering the support tray 121, and locking members 123 for locking the cover member 122 to the support tray 121. The support tray 121 is provided with support members 1211 for holding the storage item 2 in position.

The pod detaching mechanism 13 comprises a power drive 131, and actuating means, for example, movable blocks 132 symmetrically arranged at two sides and movable by the power drive 13 to unlock the locking members 123 of the pod 12. The movable blocks 132 each have retaining rods for engaging respective retaining holes of the locking members 123 so that the power drive 131 can drive the movable blocks 132 to unlock the locking members 123. The power drive 13 can be a motor drive, a gear transmission mechanism, a belt transmission mechanism, a linear slide and track assembly, a pneumatic cylinder, a hydraulic cylinder or their combination.

The displacement mechanism 14 is provided at an opposite side, namely, the bottom side of the work platform 11, comprising a plurality of vertical motion rods 141, a carrier plate 142 fixedly fastened to the top ends of the vertical motion rods 141, and transmission means (not shown) controlled to move the vertical motion rods 141 and the carrier plate 142 in and out of the accommodation chamber 110 of the work platform 11. The transmission means can be a motor drive, gear transmission mechanism, belt transmission mechanism, pneumatic cylinder, hydraulic cylinder, etc., that can move the vertical motion rods 141 and the carrier plate 142 in and out of the accommodation chamber 110 of the work platform 11.

Referring to FIGS. 2˜5, the inert gas filling system 1 is installed in the bottom side of one storage 31 of a pod storage cabinet 3, which has an openable access door 32. When a user is going to fill an inert gas in the pod 12, open the access door 32 of the storage 31, and then put the pod 12 in the storage 31 and placed on the carrier plate 142 of the displacement mechanism 14, and then close the access door 32, and then operate the power drive 131 of the pod detaching mechanism 13 to move the movable blocks 132, thereby unlocking the locking members 123.

Referring to FIGS. 6 and 7 and FIGS. 2 and 4 again, after separating of the cover member 122 from the support tray 121, the cover member 122 of the pod 12 is kept secured to the movable blocks 132 of the pod detaching mechanism 13 in such a position that the cover member 122 seals the first opening 111 of the accommodation chamber 110 of the platform 11, and then the displacement mechanism 14 is operated to lower the carrier plate 142 and the support tray 121 into the accommodation chamber 110 of the work platform 11, holding the carrier plate 142 in such a position that the carrier plate 142 seals the second opening 112 of the accommodation chamber 110 of the work platform 11. Thus, the accommodation chamber 110 is kept in an airtight status. At this time, an inert gas supply source (not shown) is connected to one of the inert gas filling ports 113 to fill an inert gas into the accommodation chamber 110 of the platform 11. The inert gas can be nitrogen gas, helium gas or neon gas. After filling of the inert gas, the vertical motion rods 141 of the displacement mechanism 14 are moved to lift the carrier plate 142 and the support tray 121 to the cover member 122, and then the power drive 131 of the pod detaching mechanism 13 is operated to move the movable blocks 132, forcing the locking members 123 from the unlocking position to the locking position to lock the cover member 122 to the support tray 121. Thereafter, open the access door 32, and then remove the pod 12 from the pod storage cabinet 3.

The aforesaid pod detaching mechanism 13 is adapted to lock/unlock the support tray 121 and the cover member 122. The power drive 131 of the pod detaching mechanism 13 can be a motor drive, screw transmission mechanism or any of a variety of equivalent means capable of moving the movable blocks 132 to shift the locking members 123 between the locking position and the unlocking position. Other equivalent means may be used to substitute for the movable blocks 132.

FIGS. 8 and 9 show an alternate form of the displacement mechanism 14. According to this embodiment, the displacement mechanism 14 is provided above the pod 12, comprising a plurality of vertical motion rods 141 and a plurality of vacuum mounts 143 respectively fixedly fastened to the bottom ends of the vertical motion rods 141.

When the user is going to fill an inert gas into the pod 12, the pod detaching mechanism 13 is operated to detach the support tray 121 and the cover member 122, and then the displacement mechanism 14 is operated to lower the motion rods 141 and to force the vacuum mounts 143 into positive engagement with the cover member 122 of the pod 12 by means of vacuum suction, and then the displacement mechanism 14 is operated to lift the motion rods 141 and the attached cover member 122, separating the cover member 122 from the support tray 121 and forcing the cover member 122 to seal the first opening 111 of the accommodation chamber 110 of the work platform 11. Thus, the accommodation chamber 110 of the work platform 11 is kept in an airtight status. The user can than fill an inert gas into the accommodation chamber 110 through the inert gas filling ports 113. After filling of a predetermined amount of the inert gas in the accommodation chamber 110, the displacement mechanism 14 is operated to return the motion rods 141 and to place the cover member 122 on the support tray 121, and then the pod detaching mechanism 13 is operated to lock the support tray 121 and the cover member 122. Thus, the user can then remove the pod 12 from the pod storage cabinet 3.

As indicated above, the present invention provides an inert gas filling system 1, which has the following features and benefits:

1. The invention blocks the accommodation chamber 110, keeping it in an airtight status. Thus, an inert gas can be filled in the accommodation chamber 110 through the inert gas filling ports 113 to reduce particle-induced friction, maintaining cleanliness in the pod 12.

2. The invention uses the inert gas filling ports 113 for filling an inert gas into the accommodation chamber 110 to control pollutants of the storage item 2 by means of the motion and flowing direction of the supplied inert gas, preventing oxidization of the storage item 2.

3. The user can start the inert gas filling operation after opened the work platform 11 or the pod storage cabinet 3 and placed the pod 12 with the storage item 2 in the pod storage cabinet 3. The operation procedure is simple and convenient.

Although particular embodiments of the invention have been described in detail for purposes of illustration, various modifications and enhancements may be made without departing from the spirit and scope of the invention. For example, vacuum mounts may be provided at the carrier plate of the displacement mechanism for securing the photomask pod. Accordingly, the invention is not to be limited except as by the appended claims. 

1. A gas filling system for filling a pod with a gas, said pod comprising a support tray, a cover member detachably covering said support tray, and locking members for locking said cover member to said support tray, said support tray having support members for holding a storage item in position, said locking members each having at least one retaining hole, the gas filling system comprising: a work platform, said work platform comprising an accommodation chamber, a first opening at a one side of said accommodation chamber, a second opening at another side of said accommodation chamber, and at least one filling port through which a gas is filled into said accommodation chamber; a pod detaching mechanism disposed in one side of said work platform, said pod detaching mechanism comprising a power drive, and a plurality of movable blocks movable by said power drive to lock/unlock said locking members of said pod, said movable blocks each having at least one retaining rod for engaging said retaining holes of said locking members; and a displacement mechanism mounted at the second opening of said work platform, said displacement mechanism comprising at least one vertical motion rod, a carrier plate fixedly fastened to said at least one vertical motion rod for holding said pod in said accommodation chamber, at least one suction mount provided at said carrier plate for securing said pod, and transmission means controllable to move said at least one vertical motion rod and said carrier plate.
 2. The gas filling system as claimed in claim 1, where in the gas to be filled in said accommodation chamber is prepared from one of an inert gas, dry air, pure air and nitrogen.
 3. The gas filling system as claimed in claim 1, wherein said power drive of said pod detaching mechanism is prepared from one of a motor drive, a gear transmission mechanism, a belt transmission mechanism, a linear slide and track assembly, a pneumatic cylinder, a hydraulic cylinder and their combination.
 4. The gas filling system as claimed in claim 1, wherein the transmission means of said displacement mechanism is prepared from one of a motor drive, a gear transmission mechanism, a belt transmission mechanism, a linear slide and track assembly, a pneumatic cylinder, a hydraulic cylinder and their combination.
 5. The gas filling system as claimed in claim 1, wherein the cover member of said pod is sealed to the first opening of said accommodation chamber of said work platform.
 6. The gas filling system as claimed in claim 1, wherein the accommodation chamber of said work platform is peripherally sealed with an airtight seal member.
 7. A pod detaching mechanism installed in one side of a work platform of a gas filling system adapted for filling a pod with a gas, said pod comprising a support tray, a cover member detachably covering said support tray, and locking members for locking said cover member to said support tray, said locking members each having at least one retaining hole, the pod detaching mechanism comprising a power drive, and a plurality of movable blocks and movable by said power drive to lock/unlock said locking members of said pod, said movable blocks each having at least one retaining rod for engaging the retaining holes of said locking members.
 8. The pod detaching mechanism as claimed in claim 7, wherein said power drive is prepared from one of a motor drive, a gear transmission mechanism, a belt transmission mechanism, a linear slide and track assembly, a pneumatic cylinder, a hydraulic cylinder and their combination.
 9. A displacement mechanism installed in a work platform of a gas filling system adapted for moving a pod, said pod comprising a support tray, a cover member detachably covering said support tray, and locking members for locking said cover member to said support tray, said locking members each having at least one retaining hole, the displacement mechanism comprising at least one vertical motion rod, a carrier plate fixedly fastened to said at least one vertical motion rod for holding said pod in said accommodation chamber, at least one suction mount provided at said carrier plate for securing said pod, and transmission means controllable to move said at least one vertical motion rod and said carrier plate.
 10. The displacement mechanism as claimed in claim 9, wherein said transmission means is prepared from one of a motor drive, a gear transmission mechanism, a belt transmission mechanism, a linear slide and track assembly, a pneumatic cylinder, a hydraulic cylinder and their combination.
 11. A gas filling system for filling a pod with a gas, said pod comprising a support tray, a cover member detachably covering said support tray, and locking members for locking said cover member to said support tray, the gas filling system comprising: a work platform, said work platform comprising an accommodation chamber for accommodating said pod and for filling of a gas in the pod stored therein; a pod detaching mechanism disposed in one side of said work platform, said pod detaching mechanism comprising a power drive, and actuating means movable by said power drive to lock/unlock said locking members of said pod; and a displacement mechanism mounted in a second side of said work platform and controllable to move said support tray of said pod relative to said cover member of said pod after unlocking of said locking members of said pod.
 12. A gas filling system for filling a pod with a gas, said pod comprising a support tray, a cover member detachably covering said support tray, and locking members for locking said cover member to said support tray, said support tray having support members for holding a storage item in position, said locking members each having at least one retaining hole, the gas filling system comprising: a pod storage cabinet, said pod storage cabinet comprising a storage; a work platform installed in said pod storage cabinet in a bottom side of said storage, said work platform comprising an accommodation chamber for accommodating said pod and for filling of a gas in the pod stored therein; a pod detaching mechanism disposed in one side of said work platform inside said pod storage cabinet, said pod detaching mechanism comprising a power drive, and actuating means movable by said power drive to lock/unlock said locking members of said pod; and a displacement mechanism mounted in a second side of said work platform inside said pod storage cabinet and controllable to move said support tray of said pod relative to said cover member of said pod after unlocking of said locking members of said pod.
 13. The gas filling system as claimed in claim 12, wherein said access door of said pod storage cabinet are peripherally sealed with airtight seal means.
 14. The gas filling system as claimed in claim 12, wherein said pod storage cabinet comprises an access door controllable to close/open said storage.
 15. The gas filling system as claimed in claim 14, wherein said storage of said pod storage cabinet are peripherally sealed with airtight seal means. 